Gray's monitor, Varanus olivaceus is a large (180 cm, >9 kg) monitor lizar known only from lowland dipterocarp forest in the east of Luzon and a few smaller adjacent islands in the Philippines, where it is locally known as the Butaan. It is largely arboreal and extremely shy. It is classed as vulnerable by the IUCN because most of its habitat has been destroyed over the last 60 years. Its diet consists mainly of fruit and snails.